Alert archive / Texas / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 147, NWS Houston/Galveston, TX

December 12, 2015Harris County, Montgomery County, Waller County, Texas

NWS Houston/Galveston, TX issued this severe thunderstorm warning at Dec 12, 2015, 6:00 PM CST for Harris County, Montgomery County, Waller County, Texas. It was in force for 30 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Dec 12, 2015, 6:00 PM CST (00:00 UTC)
Expired: Dec 12, 2015, 6:30 PM CST
In force: 30 min
Issued by: NWS Houston/Galveston, TX
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

Counties Harris County, TX, Montgomery County, TX, Waller County, TX

The radar

The Houston radar (KHGX), 84 km from the middle of the area, began a volume at 00:00 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 0.0 hours before the alert went out and 308 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1370 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 518 m above ground
0-6 km bulk shear: 53 kt
0-1 km storm-relative helicity: 266 m²/s²
0-3 km storm-relative helicity: 300 m²/s²
Significant tornado parameter: 2.4
Supercell composite: 11.1

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Houston/Galveston, TX wrote its last area forecast discussion before this severe thunderstorm warning went out at Dec 12, 5:21 PM CST, 39 minutes earlier.

Area forecast discussion, Dec 12, 5:21 PM CST, 39 minutes before

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Hazardous weather outlook, Dec 12, 4:45 PM CST, 1 hour 15 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
445 PM CST SAT DEC 12 2015

TXZ163-164-176>179-195>200-210>214-226-227-235>238-132245-
AUSTIN-BRAZORIA-BRAZOS-BURLESON-CHAMBERS-COLORADO-FORT BEND-
GALVESTON-GRIMES-HARRIS-HOUSTON-JACKSON-LIBERTY-MADISON-MATAGORDA-
MONTGOMERY-POLK-SAN JACINTO-TRINITY-WALKER-WALLER-WASHINGTON-
WHARTON-
445 PM CST SAT DEC 12 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TONIGHT

A COUPLE ROUNDS OF SHOWERS AND ISOLATED THUNDERSTORMS ARE
EXPECTED. THE FIRST DISTURBANCE WILL MOVE ACROSS THE AREA TONIGHT.
THE SECOND ONE WILL CONSIST OF A SQUALL LINE PUSHING THROUGH
BETWEEN 4 AM AND MIDDAY SUNDAY. ISOLATED STRONGER CELLS BOTH WITH
AND AHEAD OF THIS LINE COULD PRODUCE WIND DAMAGE OR TORNADOES.
RAINFALL TOTALS WILL AVERAGE 1 TO 3 INCHES WITH SOME ISOLATED
LOCATIONS RECEIVING 4 TO 6 INCHES IF TRAINING OF STORMS DEVELOP.

ELEVATED WINDS ARE EXPECTED AHEAD OF THE APPROACHING SQUALL LINE...
AND A WIND ADVISORY IS IN EFFECT FOR AREAS ALONG AND SOUTH OF
INTERSTATE 10.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE SQUALL LINE WILL DEPART THE AREA MIDDAY SUNDAY.
OTHERWISE...NO HAZARDOUS WEATHER IS EXPECTED.

.SPOTTER INFORMATION STATEMENT...

EMERGENCY MANAGERS AND STORM SPOTTERS SHOULD PREPARE FOR POSSIBLE
ACTIVATION TONIGHT THROUGH SUNDAY MORNING.

GMZ330-335-350-355-370-375-132245-
GALVESTON BAY-MATAGORDA BAY-
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM-
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM-
WATERS FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM-
WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM-
445 PM CST SAT DEC 12 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST TEXAS.

.DAY ONE...TONIGHT

SOUTH WINDS WILL STRENGTHEN AND SEAS WILL BUILD. SMALL CRAFT
ADVISORIES ARE IN EFFECT. SCATTERED PRECIPITATION IS EXPECTED
TODAY FOLLOWED BY A SQUALL LINE SUNDAY MORNING. WATERSPOUTS AND
CHAOTIC SEAS ARE POSSIBLE IN AND NEAR STORMS.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY

THE SQUALL LINE WILL DEPART THE AREA BY EARLY AFTERNOON SUNDAY.
HOWEVER WINDS AND SEAS WILL TAKE A WHILE TO SUBSIDE AND SMALL
CRAFT ADVISORIES ARE POSSIBLE FOR MOST OF THE DAY SUNDAY. ANOTHER
FRONT AND MODERATE TO STRONG OFFSHORE FLOW IS EXPECTED EARLY
WEDNESDAY. OTHERWISE...NO HAZARDOUS WEATHER IS EXPECTED..

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED.

In the hours before

Special weather statement, Dec 12, 4:31 PM CST, 1 hour 29 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
431 PM CST SAT DEC 12 2015

TXZ177-199-122300-
WALKER TX-MONTGOMERY TX-
431 PM CST SAT DEC 12 2015

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN WALKER AND
NORTHWESTERN MONTGOMERY COUNTIES UNTIL 500 PM CST...

AT 430 PM CST...DOPPLER RADAR WAS TRACKING A STRONG THUNDERSTORM NEAR
LAKE CONROE DAM...OR 7 MILES WEST OF WILLIS...MOVING NORTH AT 40 MPH.

WIND GUSTS IN EXCESS OF 40 MPH AND FUNNEL CLOUDS WILL BE POSSIBLE
WITH THIS STORM.

LOCATIONS IMPACTED INCLUDE...
WESTERN CONROE...HUNTSVILLE...WILLIS...PANORAMA VILLAGE...NEW
WAVERLY...MONTGOMERY...LAKE CONROE DAM...HUNTSVILLE STATE PARK AND
CRABBS PRAIRIE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
OFFICE IN LEAGUE CITY .

IF ON OR NEAR LAKE CONROE...GET OUT OF THE WATER AND MOVE INDOORS OR
INSIDE A VEHICLE. REMEMBER...LIGHTNING CAN STRIKE OUT TO 15 MILES
FROM THE PARENT THUNDERSTORM. IF YOU CAN HEAR THUNDER...YOU ARE
CLOSE ENOUGH TO BE STRUCK BY LIGHTNING. MOVE TO SAFE SHELTER NOW.
DO NOT BE CAUGHT ON THE WATER IN A THUNDERSTORM.

&&

LAT...LON 3034 9551 3038 9572 3085 9566 3080 9535
TIME...MOT...LOC 2230Z 191DEG 36KT 3044 9560

40

Local storm report, Dec 12, 5:01 PM CST, 59 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE HOUSTON/GALVESTON TX
501 PM CST SAT DEC 12 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0353 PM     TSTM WND DMG     4 NNW WILLIS            30.48N  95.50W
12/12/2015                   MONTGOMERY         TX   TRAINED SPOTTER

            UPROOTED TREES AND DAMAGE TO ONE BUSINESS REPORTED AT
            INTERSTATE 45 AND SHEPHERD HILL ROAD. POSSIBLE TORNADO.

&&

EVENT NUMBER HGX1500557

MH

Special weather statement, Dec 12, 5:05 PM CST, 55 minutes before

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Special weather statement, Dec 12, 5:18 PM CST, 42 minutes before

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Special weather statement, Dec 12, 5:30 PM CST, 30 minutes before

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Special weather statement, Dec 12, 5:36 PM CST, 24 minutes before

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The office that day

Everything else NWS Houston/Galveston, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Dec 12, 7:52 PM CST	Special Weather Statement	HGX	Walker	38 min
Dec 12, 8:37 PM CST	Special Weather Statement	HGX	Brazos	53 min
Dec 12, 9:02 PM CST	Flash Flood Watch	HGX	Brazos, Burleson, Grimes, Houston, Madison, Montgomery and 3 more	13 hr
Dec 12, 9:04 PM CST	Areal Flood Advisory	HGX	Austin, Brazos, Burleson, Colorado, Grimes, Madison and 1 more	4 hr
Dec 13, 1:16 AM CST	Special Weather Statement	HGX	Montgomery	44 min
Dec 13, 2:04 AM CST	Special Weather Statement	HGX	Brazoria	26 min
Dec 13, 2:20 AM CST	Special Marine Warning	HGX		40 min
Dec 13, 2:54 AM CST	Special Weather Statement	HGX	Brazos, Burleson	81 min
Dec 13, 3:50 AM CST	Special Weather Statement	HGX	Brazos, Burleson, Madison, Washington	55 min
Dec 13, 3:57 AM CST	Severe Thunderstorm Warning	HGX	Brazos, Burleson	33 min
Dec 13, 4:30 AM CST	Special Weather Statement	HGX	Austin, Brazos, Colorado, Grimes, Houston, Madison and 3 more	75 min
Dec 13, 5:57 AM CST	Special Weather Statement	HGX	Austin, Colorado, Fort Bend, Harris, Houston, Jackson and 6 more	63 min
Dec 13, 6:59 AM CST	Special Weather Statement	HGX	Fort Bend, Harris, Jackson, Liberty, Matagorda, Montgomery and 3 more	61 min
Dec 13, 7:19 AM CST	Special Marine Warning	HGX		116 min
Dec 13, 7:47 AM CST	Beach Hazards Statement	HGX	Brazoria, Chambers, Galveston, Matagorda	10 hr
Dec 13, 7:48 AM CST	Special Weather Statement	HGX	Brazoria, Chambers, Harris, Liberty, Matagorda, Polk	72 min
Dec 13, 8:21 AM CST	Special Marine Warning	HGX		24 min
Dec 13, 8:23 AM CST	Areal Flood Advisory	HGX	Brazoria, Chambers, Galveston, Harris, Liberty, Polk	112 min
Dec 13, 8:56 AM CST	Special Marine Warning	HGX		49 min
Dec 13, 8:56 AM CST	Special Weather Statement	HGX	Chambers, Galveston	64 min
Dec 13, 9:13 AM CST	Special Marine Warning	HGX		2 hr
Dec 13, 9:41 AM CST	Special Marine Warning	HGX		49 min
Dec 13, 9:46 AM CST	River Flood Warning	HGX	Liberty, Polk, San Jacinto	8 days
Dec 13, 9:46 AM CST	River Flood Warning	HGX	Brazos, Grimes, Madison	5 days
Dec 13, 10:00 AM CST	Special Marine Warning	HGX		45 min
Dec 13, 10:19 AM CST	Areal Flood Advisory	HGX	Chambers, Galveston, Liberty	56 min
Dec 13, 11:12 AM CST	Special Marine Warning	HGX		2 hr

Nearby

Severe Thunderstorm Warnings in Texas, 2015 Every severe thunderstorm warning in 2015

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.